drm/i915/adlp/fb: Prevent the mapping of redundant trailing padding NULL pages

So far the remapped view size in GTT/DPT was padded to the next aligned
offset unnecessarily after the last color plane with an unaligned size.
Remove the unnecessary padding.

Cc: Juha-Pekka Heikkila <juhapekka.heikkila@gmail.com>
Fixes: 3d1adc3d ("drm/i915/adlp: Add support for remapping CCS FBs")
Signed-off-by: Imre Deak <imre.deak@intel.com>
Reviewed-by: Juha-Pekka Heikkila <juhapekka.heikkila@gmail.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20211026225105.2783797-3-imre.deak@intel.com
(cherry picked from commit 6b6636e1)
Signed-off-by: Rodrigo Vivi <rodrigo.vivi@intel.com>

drivers/gpu/drm/i915/display/intel_display.c

@@ -848,9 +848,16 @@ unsigned int intel_remapped_info_size(const struct intel_remapped_info *rem_info
 	int i;
 
 	for (i = 0 ; i < ARRAY_SIZE(rem_info->plane); i++) {
+		unsigned int plane_size;
+
+		plane_size = rem_info->plane[i].dst_stride * rem_info->plane[i].height;
+		if (plane_size == 0)
+			continue;
+
 		if (rem_info->plane_alignment)
 			size = ALIGN(size, rem_info->plane_alignment);
-		size += rem_info->plane[i].dst_stride * rem_info->plane[i].height;
+
+		size += plane_size;
 	}
 
 	return size;

drivers/gpu/drm/i915/gt/intel_ggtt.c

@@ -1396,6 +1396,9 @@ remap_pages(struct drm_i915_gem_object *obj,
 {
 	unsigned int row;
 
+	if (!width || !height)
+		return sg;
+
 	if (alignment_pad) {
 		st->nents++;